1. Field of the Invention
The present invention concerns a reprogrammable network communication device which communicates on a network. More particularly, the present invention relates to a reprogrammable network communication device which confirms that it is being reprogrammed with a compatible image before it allows reprogramming to occur.
2. Incorporation by Reference
U.S. patent application Ser. No. 07/978,369, entitled "Method And Apparatus For Interfacing A Peripheral To A Local Area Network", now U.S. Pat. No. 5,611,046, is hereby incorporated by reference.
3. Description of the Related Art
In recent years, as local area networks (LANs) grow more complex, it has become common to upgrade network communication devices with the newest technology available. Such upgrades are easiest to perform over the LAN. For example, a network administrator can remotely alter a firmware image on a network communication device by downloading new data to the device, which then reprograms itself with the new firmware image.
A typical personal computer (PC) onto which a network administrator may log, however, may be connected to more than one-LAN. For example, a PC may be connected to both an Ethernet LAN and to a Token-ring LAN, and may function as the network administrator for both networks. Each of the LANs may in turn be connected to several reprogrammable network communication devices. Thus, in such a structure, there are multiple devices which the network administrator can potentially reprogram, and there is therefore a possibility that the network administrator might inadvertently reprogram one of those devices with an incompatible image.
The results of downloading an incompatible image can be devastating. For example, if the network administrator erroneously downloads a Token-ring image to a card connected to an Ethernet LAN, and that card then reprograms itself with the Token-ring image, it will no longer be able to communicate on an Ethernet LAN at all. This means that the card could not even be reprogrammed over the LAN--it is, quite literally, a "dead" board as far as the Ethernet LAN is concerned. Other incompatibilities, such as, for example, incompatibilities in the host interface configuration, product configuration, processor configuration and memory configuration, can result in "dead" boards.